If you are building the cabinet from scratch yourself might as well do the control panel from scratch too. If you have one or access to a router that would be great since you need it to make the slot for the t-molding and recess from underneath for the HAPP or iL competition stick like this:


By doing that you get the proper height once the joystick is installed, it really bothers me when I see HAPP/iL sticks look like stubbies

From the cost perspective you aren't really saving much and actually paying more for inferior quality arcade parts since X-Arcade makes their own HAPP knock offs in china.
KeyWiz40-ST PS2 Interface $35.95 (from groovygamegear.com)
iL 8-Way Eurojoystick $9.95 x 2 = $19.90
Happ Pushbutton with Horizontal Microswitch $1.55 x 16 = $24.80 [this will cover P1+P2]
Happ Player Imprint, White Pushbutton with Horizontal Microswitch $1.95 x 2 = $3.90 [this will cover P1+P2 start buttons]
Happ Pushbutton with Horizontal Microswitch $1.55 x 2 = $3.10 [if you care for the side buttons for pinball games]
Wiring and pack of 100 quick disconnects $10
MDF wood required to make a stick enclosure $10-15
Total so far is ~$112.65 plus shipping where as an X-Arcade dual stick is $129.95 plus shipping. In the end, you will end up with something that suits your needs 100% without having to settle and also a sense of accomplishment once your cab is done. Also you won't get any grief when you post your project thread and people posting stuff like:
"ugh... x-arcade sucks!!!"
"nice cab but fugly control panel"
"how come you didn't make your control panel from scratch?"
"only a matter of time before the joystick or buttons fail

"
etc....